The self-preoccupation and egocentrism sometimes observed in affectively ill adults may significantly interfere with their ability to understand the experiences and needs of other persons. Such a deficit in a parent could seriously interfere with rearing functions. The purpose of this research is (a) to examine role-taking and interpersonal problem-solving abilities of depressed and non-depressed mothers, (b) to examine the development of parallel abilities in their children in the first years of life, and (c) to explore correspondences beween parents' and children's capabilities and handicaps in making appropriate inferences about others' psychological states. Mother's abilities to make inferences about others' internal states are being assessed in hypothetical social problem-solving situations and in structured interactions with their child. Children's abilities are assessed in both natural and experimental environments.